With increasing development of science and technology, personal computers and networks are widely used in homes and become indispensable communication devices. For example, through network connection, personal computers in homes may be employed to exchange data, share data or print data. Nowadays, a power line communication (PLC) system is one of the most popular ways to connect many computers. In the PLC system, the electrical wires are utilized to connect these computers.
FIG. 1 schematically illustrates the architecture of a conventional broadband power line communication system. Generally, the home-use power outlets are found in many regions such as rooms, studies, living rooms, kitchens, or the like. These power outlets are connected with each other in parallel to provide AC power. In additions, the power outlets and the electric wires between these power outlets may be collectively employed to construct the broadband power line communication system. As shown in FIG. 1, the plug 105 of the personal computer 100 may be inserted into a first power outlet 110 to provide electrical power to the personal computer 100. The personal computer 100 may be in communication with another home-use computer (e.g. a notebook computer 200) through corresponding electrical wires within the power outlets.
Generally, in the broadband power line communication system, several broadband power line network devices are employed to transmit Ethernet signals at a data transmission rate higher than 10 Mbps. The network system that does not transmit Ethernet signals and the network system that transmit Ethernet signals at the data transmission rate lower than 10 Mbps are not considered as the broadband power line communication system. For brevity, in this context, the power line network devices are broadband power line network devices.
Please refer to FIG. 1 again. The network line 115 of the personal computer 100 is connected to a first power line network device 120, and the first power line network device 120 is plugged into a second power outlet 125. Similarly, the network line 215 of the notebook computer 200 is connected to a second power line network device 220, and the second power line network device 220 is plugged into a third power outlet 225. In such way, the personal computer 100 and the notebook computer 200 are in communication with each other, and the broadband power line communication system is established.
As is well known, the power outlet can provide a high AC voltage such as 110V or 220V. Consequently, the trace layout of each power line network device should comply with stringent safety regulations in order to prevent any user from directly contacting with the high AC voltage at any situation.
Therefore, there is a need of proving a power line network device for complying with the safety regulations and meeting the requirements of reduced trace layout area and reduced fabricating cost.